Inkjet printing systems include scanning type systems and single-pass systems that deliver ink to printable media through printheads. In single-pass printing systems, a printhead assembly includes multiple printheads on a print bar that is pre-filled with an internal ink supply. The print bar spans the width of the media and ejects ink as the media continually advances in a direction perpendicular to the print bar. In scanning type printing systems, printhead assemblies include a printhead integrated on a cartridge that has an internal ink supply. One or more cartridges are held by a scanning carriage that scans back and forth across the media as the media is incrementally advanced in a direction perpendicular to the scanning. In either case, the printhead assemblies (i.e., print bars pre-filled with ink, individual print cartridges) encounter water loss during shipping and storage. Water loss can result in print quality defects and reduced printhead life.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.